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1.
Inorg Chem ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39298650

RESUMEN

Chalcophosphates are an important type of infrared nonlinear optical (NLO) candidates in view of their rich anionic motifs. Here, two copper chalcophosphates Cu3PSe4 (CPSe) and Cs2CuP3S9 (CCPS) were synthesized and studied as IR NLO materials. They both feature three-dimensional polyanionic frameworks constructed by similar T2-supertetrahedra, and the structure of CCPS can be derived from CPSe via introducing Cs and substituting Se with S. This structural evolution results in phase-matchable NLO behavior, enlarged optical band gap, and enhanced laser-induced damage threshold for CCPS. These results are elucidated by structure analysis and theoretical calculations, and the increased structural anisotropy contributes to the phase matchable behavior of CCPS. This work presents a case on how to adjust NLO properties via certain structure considerations, which may be extended to more systems for obtaining high-performance NLO materials.

2.
Zhongguo Gu Shang ; 37(8): 772-8, 2024 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-39183000

RESUMEN

OBJECTIVE: To study the effect of intervertebral grafting area on the effect of single segment lumbar posterior decompression and intervertebral bone grafting fusion. METHODS: The clinical data of 52 patients who underwent single-segment lumbar posterior decompression pedicle internal fixation and bone grafting fusion from January 2020 to December 2022 were retrospective reviewed. The area of the intervertebral bone graft was measured one week postoperatively using Computed Tomography (CT), and based on the ratio of the bone graft area to the average area of the endplates, the patients were divided into three groups:17 cases in group A(the intervertebral bone graft area did not exceed the area of one pedicle) included 9 males and 8 females with an average age of (56.0±11.5) years old;15 cases in group B(the intervertebral bone graft area exceeded one pedicle but did not reach the opposite pedicle) included 10 males and 5 females with an average of (52.0±14.0) years old; 20 cases in group C (the intervertebral bone graft area exceeded the opposite pedicle) included 12 males and 8 females with an average of (49.5±12.8) years old. X-rays and CT scans were performed at 3, 6, 12 months, and the final follow-up postoperatively, the interbody fusion Brantigan scores, pain visual analogue scale (VAS), and Oswestry Disability Index (ODI) at each follow-up were recorded. RESULTS: The gender, age, and surgical segments showed no significant differences among three groups(P>0.05). There was also no significant difference in the preoperative VAS and ODI among three groups (P>0.05). All patients of three groups were followed up from 12 to 36 months. Compared with preoperative, VAS and ODI scores of three groups showed significant improvement at 1 week postoperatively and the final follow-up (P<0.05). Compared with preoperative measurements, the height of the intervertebral space was restored at 1 week postoperatively in three groups;at the final follow-up, the loss of height in the intervertebral space was less in groups B and C, and the height of the intervertebral space in group B and C was significantly higher than in group A(P<0.05). The modified Brantigan scores at 3 and 6 months postoperatively were significantly higher in group C than in groups A and B (P<0.05);at 12 months postoperatively, the scores in groups B and C were significantly higher than in group A(P<0.05);however, at the final follow-up, there was no significant difference in the modified Brantigan scores among three groups(P>0.05). The bone graft fusion rate in group C was significantly higher than in groups A and B at 3 months postoperatively(P<0.05);at 6 and 12 months postoperatively, the fusion rates in groups B and C were significantly higher than in group A(P<0.05);at the final follow-up, the fusion rate in group A was still lower than in groups B and C, but the difference among three groups was not significant(P>0.05). CONCLUSION: Single segment posterior lumbar decompression and interbody fusion surgery can significantly improve the clinical symptoms of patients with lumbar degenerative related diseases. However, as the proportion of bone grafting area increases, the early bone grafting fusion rate and fusion score of patients are significantly improved.


Asunto(s)
Trasplante Óseo , Descompresión Quirúrgica , Vértebras Lumbares , Fusión Vertebral , Humanos , Masculino , Femenino , Persona de Mediana Edad , Trasplante Óseo/métodos , Vértebras Lumbares/cirugía , Descompresión Quirúrgica/métodos , Fusión Vertebral/métodos , Estudios Retrospectivos , Adulto , Anciano , Tomografía Computarizada por Rayos X
3.
ChemSusChem ; : e202400694, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39212083

RESUMEN

Suppressing the non-radiative energy loss (ΔE3) mediated by triplet charge transfer state is crucial for high-performance organic solar cells (OSCs). Here, we decode the energy inversion through multi-scale theoretical simulation, which inhibits the non-emissive triplet (T1) state formation. However, it is mystified by the system dependence. We first demonstrate a direct relationship of "the probability of Face-on orientation (PFace-on) is proportional to the probability of energy inversion (PEI)", which is related to the function of terminal fluorination. Through Pearson's correlation coefficient and machine learning model, the useful stacking structural parameters were obtained to clarify the effect of π-bridge group on the function of terminal fluorination. Based on the molecular descriptors established, we explain that the fluorination effect is beneficial to Face-on orientation and thus energy inversion due to the enhanced intermolecular coupling. But the π-bridge inhibits this coupling with the interfacial stacking configuration appearing more "TT_IC". This work provides a directional standard for promoting energy inversion to reduce ΔE3 for the high-performance OSCs.

4.
J Biotechnol ; 393: 140-148, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39067578

RESUMEN

Cyclic nucleic acids are biologically stable against nucleic acid exonucleases due to the absence of 5' and 3' termini. Studies of cyclic nucleic acids mainly focus on cyclic single-stranded nucleic acids. Cyclic single-stranded nucleic acids are further divided into circular RNA (circRNA) and circular single-stranded DNA (cssDNA). The synthesis methods of circRNA include lasso-driven cyclization, intron-paired cyclization, intron cyclization, intron complementary pairing-driven cyclization, RNA-binding protein-driven cyclization, and artificial synthesis depending on the source. Its main role is to participate in gene expression and the treatment of some diseases. Circular single-stranded DNA is mainly synthesized by chemical ligation, template-directed enzyme ligation, and new techniques for the efficient preparation of DNA single loops and topologies based on CircLigase. It is mainly used in rolling circle amplification (RCA) technology and in the bioprotection of circular aptamers and second messengers. This review focuses on the types, synthesis methods, and applications of cyclic single-stranded nucleic acids, providing a reference for further research on cyclic single-stranded nucleic acids.


Asunto(s)
ADN de Cadena Simple , ARN Circular , ARN Circular/genética , ADN de Cadena Simple/genética , ADN de Cadena Simple/química , ADN de Cadena Simple/metabolismo , ADN Circular/genética , ADN Circular/química , Ciclización , Técnicas de Amplificación de Ácido Nucleico/métodos , Humanos
5.
Chem Commun (Camb) ; 60(58): 7475-7478, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38938189

RESUMEN

Here, we explain why the Energy Gap Law and the energy inversion related to the charge-transfer state have opposite effects on the trend of nonradiative energy loss of organic solar cells. The root is the existing condition of energy inversion. There is indeed a certain probability of energy inversion, but it will eventually be implicit or explicit as determined by the hybridization, which depends on the electron-withdrawing unit of the donor, giving rise to different stacking sites. The triplet-state hybridization leads to an explicit characteristic, while singlet-state hybridization leads to an implicit characteristic.

6.
ACS Nano ; 18(27): 17622-17629, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38922204

RESUMEN

Engineering atomic-scale defects has become an important strategy for the future application of transition metal dichalcogenide (TMD) materials in next-generation electronic technologies. Thus, providing an atomic understanding of the electron-defect interactions and supporting defect engineering development to improve carrier transport is crucial to future TMDs technologies. In this work, we utilize low-temperature scanning tunneling microscopy/spectroscopy (LT-STM/S) to elicit how distinct types of defects bring forth scattering potential engineering based on intervalley quantum quasiparticle interference (QPI) in TMDs. Furthermore, quantifying the energy-dependent phase variation of the QPI standing wave reveals the detailed electron-defect interaction between the substitution-induced scattering potential and the carrier transport mechanism. By exploring the intrinsic electronic behavior of atomic-level defects to further understand how defects affect carrier transport in low-dimensional semiconductors, we offer potential technological applications that may contribute to the future expansion of TMDs.

7.
Inorg Chem ; 63(17): 7555-7559, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38624233

RESUMEN

Noncentrosymmetric chalcogenides are promising candidates for infrared nonlinear-optical (NLO) crystals, and exploring high-performance ones is a hot topic and challengeable. Herein, the combination of AgQ4, InQ4, and SiQ4 (Q = S, Se) units with different S/Se ratios resulted in the discovery of the tetrahedral chalcogenides Ag2In2SiS4Se2 (1) and Ag2In2SiS5Se (2). They both crystallize in the monoclinic Cc space group with different local structures. Co-occupied S/Se sites only exist in 2, and the arrangement of [In2SiQ3] six-membered rings builds different helical chains and 3D [(In2SiQ6)2-]n polyanionic frameworks in 1 and 2. They show balanced NLO performances, including phase-matchable moderate NLO responses (0.7 and 0.5 × AGS) and enhanced laser-induced damage thresholds (4.5 and 5.1 × AGS). Theoretical calculations reveal that their NLO responses are predominantly contributed by the AgQ4 and InQ4 units.

8.
Health Inf Sci Syst ; 12(1): 29, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38584761

RESUMEN

Purpose: To explore the biliary and duodenal microbiota features associated with the formation and recurrence of choledocholithiasis (CDL). Methods: We prospectively recruited patients with primary (P-CDL, n = 29) and recurrent CDL (R-CDL, n = 27) for endoscopic retrograde cholangiopancreatography (ERCP). Duodenal mucosa (DM), bile and bile duct stones (BDS) samples were collected in P- and R-CDL patients. DM samples were also collected in 8 healthy controls (HC). The microbiota profile analysis was performed with 16S rRNA gene sequencing. Results: Short-course antibiotic application before ERCP showed no significant effects in alpha and beta diversities of the biliary and duodenal microbiota in CDL. Alpha diversity showed no difference between DM and bile samples in CDL. The duodenal microbial richness and diversity was lower in both P- and R-CDL than HC. The biliary microbiota composition showed a high similarity between P- and R-CDL. Fusobacterium and Enterococcus were higher abundant in DM, bile, and BDS samples of R-CDL than P-CDL, as well as Escherichia and Klebsiella in bile samples of R-CDL. The enriched duodenal and biliary bacteria in CDL were closely associated with cholecystectomy, inflammation and liver dysfunction. The bile-associated microbiota of R-CDL expressed enhanced capacity of D-glucuronide and D-glucuronate degradation, implicating an elevated level of ß-glucuronidase probably produced by enriched Escherichia and Klebsiella in bile. Conclusions: The duodenal microbiota was in an imbalance in CDL. The duodenal microbiota was probably the main source of the biliary microbiota and was closely related to CDL formation and recurrence. Enterococcus, Fusobacterium, Escherichia and Klebsiella might contribute to CDL recurrence. Clinical trials: The study was registered at the Chinese Clinical Trial Registry (https://www.chictr.org.cn/index.html, ChiCTR2000033940). Supplementary Information: The online version contains supplementary material available at 10.1007/s13755-023-00267-2.

9.
Surg Endosc ; 38(5): 2465-2474, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38456946

RESUMEN

BACKGROUND: Bile duct leaks (BDLs) are serious complications that occurs after hepatobiliary surgery and trauma, leading to rapid clinical deterioration. Endoscopic retrograde cholangiopancreatography (ERCP) is the first-line treatment for BDLs, but it is not clear which patients will respond to this therapy and which patients will require additional surgical intervention. The aim of our study was to explore the predictors of successful ERCP for BDLs. METHODS: A retrospective analysis was conducted using data from six centers' databases. All consecutive patients who were clinically confirmed as BDLs were included in the study. Collected data were demographics, disease severity, and ERCP procedure characteristics. Univariate and multivariate analysis were used to select independent predictive factors that affect the outcome of ERCP for BDLs, and a nomogram was established. Calibration and ROC curves were used to evaluate the models. RESULTS: Four hundred and forty-eight consecutive patients were clinically confirmed as BDLs and 347 were excluded. In the 101 patients included patients, clinical success was achieved in 78 patients (77.2%). In logistic multivariable regression, two independent factors were negatively associated with the success of ERCP: SIRS (OR, 0.183; 95% CI 0.039-0.864; P = 0.032) and high-grade leak (OR 0.073; 95% CI 0.010-0.539; P = 0.010). Two independent factors were positively associated with the success of ERCP: leak-bridging drainage (OR 4.792; 95% CI 1.08-21.21; P = 0.039) and cystic duct leak (OR 6.193; 95% CI 1.03-37.17; P = 0.046). The prediction model with these four factors was evaluated using a receiver-operating characteristic (ROC) curve, which demonstrated an area under the curve of 0.9351. The calibration curve showed that the model had good predictive accuracy. CONCLUSION: Leak-bridging drainage and cystic duct leak are positive predictors for the success of ERCP, while SIRS and high-grade leak are negative predictors. This prediction model with nomogram has good predictive ability and practical clinical value, and may be helpful in clinical decision-making and prognostication.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica , Nomogramas , Humanos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento , Adulto , Enfermedades de los Conductos Biliares/cirugía , Fuga Anastomótica/etiología
10.
Inorg Chem ; 63(9): 4017-4021, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38367266

RESUMEN

As one of the potential candidates of nonlinear-optical (NLO) materials, rare-earth chalcophosphates have demonstrated promising properties. Here, KREP2S6 (RE = Sm, Gd, Tb, Dy) were synthesized using the facile RE2O3-B-S solid-state method. They crystallize with a monoclinic chiral P21 structure, and their layer structures are built by isolated ethane-like P2S6 dimers and RES8 bicapped trigonal prisms built {[RE2S15]24-}∞ layers. By comparing the structures with related ones, the change of the alkali metal or RE3+ ions can cause structural transformation. Their band gaps are tunable between 2.58 and 3.79 eV, and their powder samples exhibit good NLO properties. Theoretical calculations suggest that the NLO properties are mainly contributed by P2S6 units and {[RE2S15]24-}∞ layers synergistically, in which {[RE2S15]24-}∞ layers and P2S6 units dominate the contribution to the band gap and second-harmonic-generation response, respectively. This work enriches the application of rare-earth chalcophosphates as NLO materials.

11.
FASEB J ; 38(5): e23501, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38411462

RESUMEN

In the adult mammalian brain, new neurons are continuously generated from neural stem cells (NSCs) in the subventricular zone (SVZ)-olfactory bulb (OB) pathway. YAP, a transcriptional co-activator of the Hippo pathway, promotes cell proliferation and inhibits differentiation in embryonic neural progenitors. However, the role of YAP in postnatal NSCs remains unclear. Here, we showed that YAP was present in NSCs of the postnatal mouse SVZ. Forced expression of Yap promoted NSC maintenance and inhibited differentiation, whereas depletion of Yap by RNA interference or conditional knockout led to the decline of NSC maintenance, premature neuronal differentiation, and collapse of neurogenesis. For the molecular mechanism, thyroid hormone receptor-interacting protein 6 (TRIP6) recruited protein phosphatase PP1A to dephosphorylate LATS1/2, therefore inducing YAP nuclear localization and activation. Moreover, TRIP6 promoted NSC maintenance, cell proliferation, and inhibited differentiation through YAP. In addition, YAP regulated the expression of the Sonic Hedgehog (SHH) pathway effector Gli2 and Gli1/2 mediated the effect of YAP on NSC maintenance. Together, our findings demonstrate a novel TRIP6-YAP-SHH axis, which is critical for regulating postnatal neurogenesis in the SVZ-OB pathway.


Asunto(s)
Proteínas Hedgehog , Células-Madre Neurales , Animales , Ratones , Neuronas , Neurogénesis , Encéfalo , Mamíferos
12.
Nanotechnology ; 35(12)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38061057

RESUMEN

In this article, a 0.7 nm thick monolayer MoS2nanosheet gate-all-around field effect transistors (NS-GAAFETs) with conformal high-κmetal gate deposition are demonstrated. The device with 40 nm channel length exhibits a high on-state current density of ~410µAµm-1with a large on/off ratio of 6 × 108at drain voltage = 1 V. The extracted contact resistance is 0.48 ± 0.1 kΩµm in monolayer MoS2NS-GAAFETs, thereby showing the channel-dominated performance with the channel length scaling from 80 to 40 nm. The successful demonstration of device performance in this work verifies the integration potential of transition metal dichalcogenides for future logic transistor applications.

13.
Ying Yong Sheng Tai Xue Bao ; 34(10): 2619-2628, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37897268

RESUMEN

Determining the differences of water use characteristics of a tree species with different origins (natural forests and introduced plantations) is significantly important for forest sustainable management. Pinus sylvestris var. mongolica is an important tree species of afforestation in the 'Three North' project in China. In this study, with Pinus sylvestris var. mongolica from two origins, we monitored the sap flow velocity of sapwood (Js) of trees by thermal dissipation sap flow probes, and analyzed the relationship between water transportation and the environmental factors during the growing season. The results showed that under the typical sunny day, daily sap flow velocity (Js-daily) of trees from plantations was significantly higher than that from natural forests. The mean value of Js-daily was 132.98 and 114.86 cm·d-1 for the two origins, respectively. Trees from plantations showed higher water transportation potential than natural forests. Vapor pressure deficit (VPD) mainly showed the driving effect on the water use process of trees from natural forests. In the plantations, there was an obvious threshold effect, and the inflection point of VPD was about 1.91 kPa, with the boundary function of Js-hour increased to the maximum of 17.88 cm·h-1. Atmospheric driven transpiration potential (Js-hour/VPD) of P. sylvestris var. mongolica trees with two origins decreased with the aggravation of soil drought, but sensitivity to drought was higher in the plantations than in the natural forests, suggesting the strong ability of Pinus sylvestris var. mongolica to regulate water use process.


Asunto(s)
Pinus sylvestris , Pinus , Pinus sylvestris/fisiología , Agua/análisis , Bosques , Árboles , Suelo , China
14.
BMC Gastroenterol ; 23(1): 344, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798726

RESUMEN

BACKGROUND AND OBJECTIVE: For high-risk elderly patients with chronic diseases, endoscopic stone removal for large common bile duct stones is associated with a high risk of adverse events and incomplete stone removal. The aim of this study was to investigate whether the treatment strategy of short-term biliary plastic stent placement followed by elective endoscopic stone removal is more effective and safer than immediate endoscopic stone removal. METHODS: The data of 262 high-risk elderly patients who received endoscopic retrograde cholangiopancreatography (ERCP) for large common bile duct (CBD) stones from 2017 to 2022 were retrospectively analyzed. The patients were divided into group A (immediate stone removal) and group B (stent drainage + elective stone removal). The baseline data of the 2 groups were matched 1:1 by propensity score matching. The stone clearance rate, ERCP procedure time, total hospital stay, and procedure-related adverse events were compared between the matched groups. In group B, stone size before and after stent placement, hospital stay, procedure time and adverse events of two ERCPs were compared. RESULTS: A total of 57 pairs of patients were successfully matched between the 2 groups. The stone clearance rate in group B was higher than that in group A (89.5% vs. 75.3, P = 0.049). The total hospital stay in group B was longer than that in group A (11.86 ± 3.912 d vs. 19.14 ± 3.176 d, P<0.001). The total adverse event rate in group A was higher than that in group B (29.8% vs. 12.3%, P = 0.005). The incidence of cholangitis/cholecystitis after ERCP was significantly higher in group A than in group B (7.0% vs. 0.9% P = 0.029). There was no significant difference in the incidence of post-ERCP pancreatitis, bleeding, pneumonia, and cardio-cerebrovascular events between the 2 groups. There were no perforation cases in either group. After plastic biliary stent placement in group B, the stone size was significantly smaller than before stent placement (1.59 ± 0.544 cm vs. 1.95 ± 0.543 cm, P < 0.001), and there was no significant difference in the total adverse event incidence between the two ERCP procedures (18.8% vs. 10.9%, P = 0.214). CONCLUSION: For high-risk elderly patients with large CBD stones, the treatment strategy involving temporary placement of plastic stent and elective endoscopic stone removal is safer and more effective than immediate stone removal.


Asunto(s)
Coledocolitiasis , Cálculos Biliares , Humanos , Anciano , Estudios Retrospectivos , Conducto Colédoco , Resultado del Tratamiento , Cálculos Biliares/cirugía , Cálculos Biliares/etiología , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Esfinterotomía Endoscópica/efectos adversos , Coledocolitiasis/cirugía , Coledocolitiasis/etiología
15.
World J Gastroenterol ; 29(20): 3157-3167, 2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37346159

RESUMEN

BACKGROUND: It has been confirmed that three-dimensional (3D) imaging allows easier identification of bile duct anatomy and intraoperative guidance of endoscopic retrograde cholangiopancreatography (ERCP), which reduces the radiation dose and procedure time with improved safety. However, current 3D biliary imaging does not have good real-time fusion with intraoperative imaging, a process meant to overcome the influence of intraoperative respiratory motion and guide navigation. The present study explored the feasibility of real-time continuous image-guided ERCP. AIM: To explore the feasibility of real-time continuous image-guided ERCP. METHODS: We selected 2 3D-printed abdominal biliary tract models with different structures to simulate different patients. The ERCP environment was simulated for the biliary phantom experiment to create a navigation system, which was further tested in patients. In addition, based on the estimation of the patient's respiratory motion, preoperative 3D biliary imaging from computed tomography of 18 patients with cholelithiasis was registered and fused in real-time with 2D fluoroscopic sequence generated by the C-arm unit during ERCP. RESULTS: Continuous image-guided ERCP was applied in the biliary phantom with a registration error of 0.46 mm ± 0.13 mm and a tracking error of 0.64 mm ± 0.24 mm. After estimating the respiratory motion, 3D/2D registration accurately transformed preoperative 3D biliary images to each image in the X-ray image sequence in real-time in 18 patients, with an average fusion rate of 88%. CONCLUSION: Continuous image-guided ERCP may be an effective approach to assist the operator and reduce the use of X-ray and contrast agents.


Asunto(s)
Sistema Biliar , Colangiopancreatografia Retrógrada Endoscópica , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Sistema Biliar/diagnóstico por imagen , Conductos Biliares/diagnóstico por imagen , Conductos Biliares/cirugía , Medios de Contraste , Fluoroscopía
16.
ACS Nano ; 17(13): 12208-12215, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37350684

RESUMEN

Because of the intrinsic low carrier density of monolayer two-dimensional (2D) materials, doping is crucial for the performance of underlap top-gated 2D devices. However, wet etching of a high-k (dielectric constant) dielectric layer is difficult to implement without causing performance deterioration on the devices; therefore, finding a suitable spacer doping technique for 2D devices is indispensable. In this study, we developed a remote doping (RD) method in which defective SiOx can remotely dope the underlying high-k capped 2D regions without directly contacting these materials. This method achieved a doping density as high as 1.4 × 1013 cm-2 without reducing the mobility of the doped materials; after 1 month, the doping concentration remained as high as 1.2 × 1013 cm-2. Defective SiOx can be used to dope most popular 2D transition-metal dichalcogenides. The low-k properties of SiOx render it ideal for spacer doping, which is very attractive from the perspective of circuit operation. In our experiments, MoS2 and WS2 underlap top-gate devices exhibited 10× and 200× increases in their on-currents, respectively, after being doped with SiOx. These results indicate that SiOx doping can be conducted to manufacture high-performance 2D devices.

17.
Chem Commun (Camb) ; 59(47): 7212-7215, 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37219366

RESUMEN

ITIC-series nonfullerene organic photovoltaics (NF OPVs) have realized the simultaneous increases of the short-circuit current density (JSC) and open-circuit voltage (VOC), called the positive correlation between JSC and VOC, which could improve the power conversion efficiency (PCE). However, it is complicated to predict the formation of positive correlation in devices through simple calculations of single molecules due to their dimensional differences. Here, a series of symmetrical NF acceptors blended with the PBDB-T donor were chosen to establish an association framework between the molecular modification strategy and positive correlation. It can be found that the positive correlation is modification site-dependent following the energy variation at the different levels. Furthermore, to illustrate a positive correlation, the energy gap differences (ΔEg) and the energy level differences of the lowest unoccupied molecular orbitals (ΔELUMO) between the two changed acceptors were proposed as two molecular descriptors. Combined with the machine learning model, the accuracy of the proposed descriptor is more than 70% for predicting the correlation, which verifies the reliability of the prediction model. This work establishes the relative relationship between two molecular descriptors with different molecular modification sites and realizes the prediction of the trend of efficiency. Therefore, future research should focus on the simultaneous enhancement of photovoltaic parameters for high-performance NF OPVs.


Asunto(s)
Aprendizaje Automático , Reproducibilidad de los Resultados
18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-981257

RESUMEN

Objective To investigate the treatment outcomes,prognosis,and risk factors of treatment failure of peritoneal dialysis associated peritonitis (PDAP) caused by Klebsiella pneumoniae,and thus provide clinical evidence for the prevention and treatment of this disease. Methods The clinical data of PDAP patients at four peritoneal dialysis centers from January 1,2014 to December 31,2019 were collected retrospectively.The treatment outcomes and prognosis were compared between the patients with PDAP caused by Klebsiella.pneumoniae and that caused by Escherichia coli.Kaplan-Meier method was employed to establish the survival curve of technical failure,and multivariate Logistic regression to analyze the risk factors of the treatment failure of PADP caused by Klebsiella pneumoniae. Results In the 4 peritoneal dialysis centers,1034 cases of PDAP occurred in 586 patients from 2014 to 2019,including 21 cases caused by Klebsiella pneumoniae and 98 cases caused by Escherichia coli.The incidence of Klebsiella pneumoniae caused PDAP was 0.0048 times per patient per year on average,ranging from 0.0024 to 0.0124 times per patient per year during 2014-2019.According to the Kaplan-Meier survival curve,the technical failure rate of Klebsiella pneumoniae caused PDAP was higher than that of Escherichia coli caused PDAP (P=0.022).The multivariate Logistic regression model showed that long-term dialysis was an independent risk factor for the treatment failure of Klebsiella pneumoniae caused PDAP (OR=1.082,95%CI=1.011-1.158,P=0.023).Klebsiella pneumoniae was highly sensitive to amikacin,meropenem,imipenem,piperacillin,and cefotetan,and it was highly resistant to ampicillin (81.82%),cefazolin (53.33%),tetracycline (50.00%),cefotaxime (43.75%),and chloramphenicol (42.86%). Conclusion The PDAP caused by Klebsiella pneumoniae had worse prognosis than that caused by Escherichia coli,and long-term dialysis was an independent risk factor for the treatment failure of Klebsiella pneumoniae caused PDAP.


Asunto(s)
Humanos , Klebsiella pneumoniae , Estudios Retrospectivos , Antibacterianos/uso terapéutico , Diálisis Peritoneal/efectos adversos , Peritonitis/tratamiento farmacológico , Factores de Riesgo , Insuficiencia del Tratamiento , Escherichia coli
19.
Front Surg ; 9: 989061, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36303850

RESUMEN

Background and aim: The number of elderly patients with biliary stones is increasing. Endoscopic retrograde cholangiography (ERCP) is considered to be an effective treatment for biliary stones. Having a sound knowledge of the risk factors can help reduce the incidence and severity of complications for ERCP. Furthermore, limited research has been published on patients aged over 85 years undergoing endoscopic biliary stone removal. This study aims to determine the risk factors that lead to complications of ERCP in patients over 85 years of age. Methods: This was a single-center retrospective study. We analyzed 156 patients aged ≥ 85 years with biliary stones who underwent their first ERCP at Chinese PLA General Hospital from February 2002 to March 2021. Logistic regression models were employed to identify the independent risk factors for complications. Results: A total of 13 patients (8.3%) had complications. Thereinto, pancreatitis, cholangitis, bleeding, and other complications occurred in 4 cases (2.6%), 1 cases (0.6%), 4 cases (2.6%), and 4 cases (2.6%), respectively. There was no perforation or death related to ERCP. Independent risk factors for complications were acute biliary pancreatitis (ABP) (P = 0.017) and Charlson Comorbidity Index (CCI) (P = 0.019). Significantly, reasons for incomplete stone removal at once were large stone (>10 mm) (P < 0.001) and higher acute physiology and chronic health evaluation scoring system (APACHE-II) (P = 0.005). Conclusions: ERCP was recommended with caution in patients ≥ 85 years of age with ABP or higher CCI undergoing endoscopic biliary stone removal. In patients with ABP without cholangitis or biliary obstruction we recommend against urgent (within 48 h) ERCP. Patients with higher CCI who can tolerate ERCP can undergo rapid ERCP biliary stenting or nasobiliary implantation with later treatment of stones, and patients who cannot tolerate ERCP are treated promptly with PTCD and aggressive conservative treatment.

20.
ACS Nano ; 16(9): 14942-14950, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36094410

RESUMEN

Scaling of monolayer transition metal dichalcogenide (TMD) field-effect transistors (FETs) is an important step toward evaluating the application space of TMD materials. Although some work on ultrashort channel monolayer (ML) TMD FETs has been published, there exist no comprehensive studies that assess their performance in a statistically relevant manner, providing critical insights into the impact of the device geometry. Part of the reason for the absence of such a study is the substantial variability of TMD devices when processes are not carefully controlled. In this work, we show a statistical study of ultrashort channel double-gated ML WS2 FETs exhibiting excellent device performance and limited device-to-device variations. From a detailed analysis of cross-sectional scanning transmission electron microscopy (STEM) images and careful technology computer aided design (TCAD) simulations, we evaluated, in particular, an unexpected deterioration of the subthreshold characteristics for our shortest devices. Two potential candidates for the observed behavior were identified, i.e., buckling of the TMD on the substrate and loss of gate control due to the source geometry and the high-k dielectric between the metal gate and the metal source electrode.

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